Ruby 3.4 support?

[voxik]

Trying to run rspec-rails test suite against Ruby 3.4, I encounter test failures such as:

   8) be_a_new matcher #with right class and new record with composable matchers one attribute is a composable matcher fails
     Failure/Error:
       expect {
         expect(record).to be_a_new(record.class).with(
           foo: a_string_matching("bar"))
       }.to raise_error("attribute {\"foo\"=>(a string matching \"bar\")} was not set on #{record.inspect}")

       expected Exception with "attribute {\"foo\"=>(a string matching \"bar\")} was not set on #<#<Class:0x00007fe77b608208>:0x00007fe77b756c68 @attributes={foo: \"foo\", bar: \"bar\"}>", got #<RSpec::Expectations::ExpectationNotMetError: attribute {"foo" => (a string matching "bar")} was not set on #<#<Class:0x00007fe77b608208>:0x00007fe77b756c68 @attributes={foo: "foo", bar: "bar"}>> with backtrace:
         # ./spec/rspec/rails/matchers/be_a_new_spec.rb:75:in 'block (7 levels) in <top (required)>'
         # ./spec/rspec/rails/matchers/be_a_new_spec.rb:77:in 'block (6 levels) in <top (required)>'
         # ./spec/spec_helper.rb:83:in 'block (3 levels) in <top (required)>'
         # ./spec/spec_helper.rb:77:in 'block (2 levels) in <top (required)>'
     # ./spec/rspec/rails/matchers/be_a_new_spec.rb:77:in 'block (6 levels) in <top (required)>'
     # ./spec/spec_helper.rb:83:in 'block (3 levels) in <top (required)>'
     # ./spec/spec_helper.rb:77:in 'block (2 levels) in <top (required)>'

The error message seems to be originating from here:

rspec-rails/lib/rspec/rails/matchers/be_a_new.rb

Lines 29 to 43 in 609bb83

	def failure_message
	[].tap do |message|
	unless actual.is_a?(expected) && actual.new_record?
	message << "expected #{actual.inspect} to be a new #{expected.inspect}"
	end
	unless attributes_match?(actual)
	describe_unmatched_attributes = surface_descriptions_in(unmatched_attributes)
	if unmatched_attributes.size > 1
	message << "attributes #{describe_unmatched_attributes.inspect} were not set on #{actual.inspect}"
	else
	message << "attribute #{describe_unmatched_attributes.inspect} was not set on #{actual.inspect}"
	end
	end
	end.join(' and ')
	end

Specifically the #{describe_unmatched_attributes.inspect}. Here are some details from binding.irb:

rom: /builddir/build/BUILD/rubygem-rspec-rails-7.1.0-build/rspec-rails-7.1.0/usr/share/gems/gems/rspec-rails-7.1.0/lib/rspec/rails/matchers/be_a_new.rb @ line 36 :

    31:             unless actual.is_a?(expected) && actual.new_record?
    32:               message << "expected #{actual.inspect} to be a new #{expected.inspect}"
    33:             end
    34:             unless attributes_match?(actual)
    35:               describe_unmatched_attributes = surface_descriptions_in(unmatched_attributes)
 => 36:               binding.irb
    37:               if unmatched_attributes.size > 1
    38:                 message << "attributes #{describe_unmatched_attributes.inspect} were not set on #{actual.inspect}"
    39:               else
    40:                 message << "attribute #{describe_unmatched_attributes.inspect} was not set on #{actual.inspect}"
    41:               end

irb(#<RSpec::Rails::Matchers::BeA...):001> p unmatched_attributes
{"foo" => #<RSpec::Matchers::BuiltIn::Match:0x00007fa0e04f40b0 @expected="bar", @expected_captures=nil, @matcher_name=:a_string_matching>}
=> {"foo" => #<RSpec::Matchers::BuiltIn::Match:0x00007fa0e04f40b0 @expected="bar", @expected_captures=nil, @matcher_name=:a_string_matching>}
irb(#<RSpec::Rails::Matchers::BeA...):002> p surface_descriptions_in(unmatched_attributes)
{"foo" => (a string matching "bar")}
=> {"foo" => (a string matching "bar")}
irb(#<RSpec::Rails::Matchers::BeA...):003> 

Obviously Ruby 3.4 changes the Hash formatting adding two spaces around hash rocket. The question is how to fix this. Several options:

1. Only the test cases are adjusted
   • Just add optional spaces
   • Something more elaborated, with Hash#inspect
2. The backward compatibility of the output is kept, therefore tests stays but the error message is formatted differently

BTW I find the hash like formatting with the brackets a bit unfortunate.

https://github.com/rspec/rspec/blob/60a7a65e195953196fb8d1836257909c56d2da85/rspec-expectations/lib/rspec/matchers/composable.rb#L162

[JonRowe]

We typically add conditions around output to show the differences between Ruby versions.